用java轻松操作properties文件 -凯发k8网页登录

发个例子大家自己看哈.
package control;

import java.io.bufferedinputstream;
import java.io.fileinputstream;
import java.io.fileoutputstream;
import java.io.ioexception;
import java.io.inputstream;
import java.io.outputstream;
import java.util.enumeration;
import java.util.properties;

public class testmain {
 
 //根据key读取value
 public static string readvalue(string filepath,string key) {
  properties props = new properties();
        try {
         inputstream in = new bufferedinputstream (new fileinputstream(filepath));
         props.load(in);
         string value = props.getproperty (key);
            system.out.println(key value);
            return value;
        } catch (exception e) {
         e.printstacktrace();
         return null;
        }
 }
 
 //读取properties的全部信息
    public static void readproperties(string filepath) {
     properties props = new properties();
        try {
         inputstream in = new bufferedinputstream (new fileinputstream(filepath));
         props.load(in);
            enumeration en = props.propertynames();
             while (en.hasmoreelements()) {
              string key = (string) en.nextelement();
                    string property = props.getproperty (key);
                    system.out.println(key property);
                }
        } catch (exception e) {
         e.printstacktrace();
        }
    }

    //写入properties信息
    public static void writeproperties(string filepath,string parametername,string parametervalue) {
     properties prop = new properties();
     try {
      inputstream fis = new fileinputstream(filepath);
            //从输入流中读取属性列表（键和元素对）
            prop.load(fis);
            //调用 hashtable 的方法 put。使用 getproperty 方法提供并行性。
            //强制要求为属性的键和值使用字符串。返回值是 hashtable 调用 put 的结果。
            outputstream fos = new fileoutputstream(filepath);
            prop.setproperty(parametername, parametervalue);
            //以适合使用 load 方法加载到 properties 表中的格式，
            //将此 properties 表中的属性列表（键和元素对）写入输出流
            prop.store(fos, "update '" parametername "' value");
        } catch (ioexception e) {
         system.err.println("visit " filepath " for updating " parametername " value error");
        }
    }

    public static void main(string[] args) {
     readvalue("info.properties","url");
        writeproperties("info.properties","age","21");
        readproperties("info.properties" );
        system.out.println("ok");
    }
}